Superstatistics in hydrodynamic turbulence
نویسنده
چکیده
Superstatistics is a ‘statistics of a statistics’ relevant for driven nonequilibrium systems with fluctuating intensive parameters. It contains Tsallis statistics as a special case. We show that probability density functions of velocity differences and accelerations measured in Eulerian and Lagrangian turbulence experiments are well reproduced by simple superstatistics models. We compare fits obtained for lognormal superstatistics and χ2-superstatistics (= Tsallis statistics).
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